1. Technical Field
The present invention relates to a device and a method for detecting a tire position.
2. Description of the Related Art
Generally, there are a vehicle wheel and a tire of transferring a torque to a vehicle at the time of braking and driving and reducing impact, or the like, transferred from a road surface while supporting a load applied to the vehicle.
The tire is integrally rotated with the vehicle wheel while being inserted into the vehicle wheel so as to absorb impact applied to the road surface and appropriately prevent sliding on the road surface at the time of braking, driving, and rotating. To this end, an air pressure of the tire needs to be constantly maintained at all times according to an external change and a traveling state.
The tire is mounted with an air injection valve protruded to the outside of the tire while communicating with an inner portion of the tire so as to appropriately inject air from the outside so as to constantly maintain the air pressure and the inner portion of the tire is provided with a tire pressure measure system (hereinafter, referred to as ‘TPMS’) so as to monitor a current air pressure state.
In this case, the TPMS first detects positions of each tire of the vehicle and checks rotational force, air pressure, temperature, or the like, of the tire by using sensors attached to each tire to detect a stable state of the tire.
Therefore, for the driving of the TPMS, a demand for an auto location function of automatically recognizing and differentiating positions of each tire has been increased. When the pressure of the tire is out of a normal level, the auto location function informs a driver whether tires at any position are out of the normal pressure.
Numerous methods for mounting the auto location function in the TPMS have been derived.
For example, in the device and method for detecting a tire position according to the prior art, a transmitter having sensors such as a pressure sensor, or the like, is directly mounted in TPMSs attached to each tire.
Further, each transmitter may be configured to transmit identification signals (hereinafter, referred to as “ID signals”) capable of identifying locations together with the pressure signal.
In addition, a main body of a vehicle is provided with a receiver including at least one antenna, wherein the receiver may receive the ID signals through the antenna from each transmitter.
The device for detecting a tire position according to the prior art may be configured to have a reference ID signal registered in the receiver. In this case, each reference ID signal matches with the ID signals from one of the transmitters and is associated with the positions of the transmitters.
Therefore, the receiver may be operated to compare the received ID signals with the reference ID signals registered therein and may identify the transmitters transmitting the ID signals when the ID signals match with the reference ID signals.
However, the device for detecting a tire position according to the prior art having the above-mentioned configuration needs to previously register the ID signals matching with the corresponding transmitter as the reference ID signals within the receiver by connecting the positions of the corresponding transmitters of the vehicle (that is, a vehicle wheel mounted with the corresponding transmitters) with the ID signals. In addition, when the exchange of the tires or the position change of the tires is performed, there is a need to update the reference ID signals within the receiver.
In this case, the position identification process may be complicated and cumbersome and much time may be consumed.
As another method, there is a method for discriminating positions of tires by analyzing signals selectively transmitted to the specific TPMS from LF transmitters mounted near each tire and RF signals transmitted from a sensor module of the TPMS in response to the selectively transmitted signals.
In this case, it is cumbersome to connect signal lines and mounting the LF transmitters around each tire and the installation cost of the system is expensive.
As another method, there is a method for mounting sensors detecting RF signal strength transmitted from each transmitter for each receiver so as to identify the positions (for example, position detections of a front wheel and a rear wheel) of the tires according to the detected RF signal strength of each transmitter.
As described above, the accuracy of the tire position identification according to the RF signal strength may be degraded due to the interference of the surrounding RF signals, or the like.
Therefore, a need exists for a device for rapidly and precisely detecting a tire position at low cost without the separate ID information and a method thereof.